path: root/mm/huge_memory.c
diff options
authorDan Williams <dan.j.williams@intel.com>2017-11-29 16:10:18 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2017-11-29 18:40:42 -0800
commitc7da82b894e9eef60a04a15f065a8502341bf13b (patch)
treec59fd3cca98b6247bcd36f2cea370c3ce746b4e2 /mm/huge_memory.c
parentmm: replace pud_write with pud_access_permitted in fault + gup paths (diff)
mm: replace pmd_write with pmd_access_permitted in fault + gup paths
The 'access_permitted' helper is used in the gup-fast path and goes beyond the simple _PAGE_RW check to also: - validate that the mapping is writable from a protection keys standpoint - validate that the pte has _PAGE_USER set since all fault paths where pmd_write is must be referencing user-memory. Link: http://lkml.kernel.org/r/151043111049.2842.15241454964150083466.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: "Jérôme Glisse" <jglisse@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/huge_memory.c')
1 files changed, 2 insertions, 2 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 4fe2491056a0..05b729f45e8a 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -877,7 +877,7 @@ struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr,
WARN_ONCE(flags & FOLL_COW, "mm: In follow_devmap_pmd with FOLL_COW set");
- if (flags & FOLL_WRITE && !pmd_write(*pmd))
+ if (!pmd_access_permitted(*pmd, flags & FOLL_WRITE))
return NULL;
if (pmd_present(*pmd) && pmd_devmap(*pmd))
@@ -1393,7 +1393,7 @@ out_unlock:
static inline bool can_follow_write_pmd(pmd_t pmd, unsigned int flags)
- return pmd_write(pmd) ||
+ return pmd_access_permitted(pmd, WRITE) ||
((flags & FOLL_FORCE) && (flags & FOLL_COW) && pmd_dirty(pmd));